WO2018191853A1 - Monitoring control method and system for load capability of battery - Google Patents

Abstract

A monitoring control method and system (10) for the load capability of a battery. The system comprises a control unit (11) and a measurement load unit (12). The control unit and the measurement load unit are respectively connected in parallel to a battery (20) to be tested. The measurement load unit comprises a measurement load (121) and a measurement load switch drive circuit (122) connected to the measurement load. The measurement load switch drive circuit is connected to the control unit, and is used for receiving a first control signal sent by the control unit and controlling, according to the first control signal, the measurement load to be connected or disconnected to the battery. By means of the monitoring control method and system for the load capability of a battery, the floating voltage of the battery can be effectively avoided, the accuracy of the voltage detection of the battery can be improved, and the remaining capacity of the battery can be more stably displayed.

Description

Method and system for monitoring and controlling battery load capacity Technical field

The present application relates to the field of battery monitoring technologies, and in particular, to a method and system for monitoring and controlling battery load capacity.

Background technique

As a basic DC power supply in electronic equipment, the battery must be monitored in real time for the output voltage and remaining capacity of the battery to prevent the system from being unstable or abnormal.

In the prior art as shown in FIG. 1, the voltage value is sampled by means of resistance voltage division, and then digital-to-analog conversion is performed to calculate the output voltage value of the battery, and finally, based on the output voltage of the battery and the charge-discharge curve of the battery. The remaining capacity of the battery.

In the process of implementing the present application, the inventors have found that at least the following problems exist in the prior art: the prior art does not consider the influence of the actual internal resistance of the battery on the output voltage value of the battery, and it is difficult to accurately measure the output voltage of the battery, thereby failing to stabilize. The ground shows the remaining capacity of the battery.

Summary of the invention

The present application provides a monitoring and control method and system for battery load capacity, which can stably display the remaining capacity of the battery based on accurately measuring the output voltage of the battery.

In a first aspect, an embodiment of the present application provides a monitoring and control system for battery load capacity, the system comprising:

a control unit and a measurement load unit, wherein the control unit and the measurement load unit are respectively connected in parallel with the battery to be detected; wherein

The measuring load unit includes a measuring load and a measured load switch driving circuit connected to the measuring load;

The measuring load switch driving circuit is connected to the control unit for receiving the control unit Transmitting a first control signal, and controlling the measurement load to communicate with or disconnect from the battery according to the first control signal;

The control unit is configured to acquire a first output voltage value of the battery when controlling the measurement load to be disconnected from the battery, and acquire a quantity of the battery when controlling the measurement load to communicate with the battery And outputting a voltage value, and determining a resistance value of the internal resistance of the battery according to the first output voltage value, the second output voltage value, and a resistance value of the measurement load; and further, according to the first output a voltage value, the second output voltage value, a resistance value of an internal resistance of the battery, a quiescent current value flowing through the control unit, and a resistance value of the measurement load, and determined in combination with a discharge curve of the battery The remaining capacity of the battery.

Wherein the measuring load switch driving circuit comprises: a first three-terminal controllable switching element and a first resistor;

The first pole of the first three-terminal controllable switching element is connected to the positive terminal of the battery through the measuring load;

The second pole of the first three-terminal controllable switching element is connected to the negative terminal of the battery;

The control pole of the first three-terminal controllable switching element is connected to the control unit through the first resistor, and is configured to receive a first control signal sent by the control unit, and control the location according to the first control signal The first pole of the first three-terminal controllable switching element and the second pole of the first three-terminal controllable switching element are turned on or off, thereby controlling the measuring load to communicate with or disconnect from the battery.

Wherein the system further comprises: a first load unit in parallel with the battery;

The first load unit includes a first load and a first load switch drive circuit, and the first load switch drive circuit is coupled to the control unit for receiving a second control signal sent by the control unit, and according to the The second control signal controls the first load to be in communication with or disconnected from the battery;

The control unit is further configured to control the measurement load to be disconnected from the battery and the first load is in communication with the battery, and acquire a third output voltage value of the battery, and according to the first output voltage The value, the third output voltage value, and the resistance of the internal resistance determine an impedance value of the first load.

The first load switch driving circuit includes: a second three-terminal controllable switching element and a second resistor;

The first pole of the second three-terminal controllable switching element is connected to the positive terminal of the battery through the first load;

The second pole of the second three-terminal controllable switching element is connected to the negative terminal of the battery;

a control pole of the second three-terminal controllable switching element is connected to the control unit by the second resistor, for receiving a second control signal sent by the control unit, and controlling the second control signal according to the second control signal The first pole of the second three-terminal controllable switching element and the second pole of the second three-terminal controllable switching element are turned on or off, thereby controlling the first load to communicate with or disconnect from the battery.

Wherein the system further comprises: a second load unit in parallel with the battery;

The second load unit includes a second load and a second load switch drive circuit, and the second load switch drive circuit is coupled to the control unit for receiving a third control signal sent by the control unit, and according to the The third control signal controls the second load to be connected or disconnected from the battery;

The control unit is further configured to control that the measurement load and the first load are both disconnected from the battery and the second load is in communication with the battery, and acquire a fourth output voltage value of the battery, and And determining an impedance value of the second load according to the first output voltage value, the fourth output voltage value, and the resistance of the internal resistance.

The second load switch driving circuit includes: a third three-terminal controllable switching element and a third resistor;

The first pole of the third three-terminal controllable switching element is connected to the positive terminal of the battery through the second load;

The second pole of the third three-terminal controllable switching element is connected to the negative terminal of the battery;

a control pole of the third three-terminal controllable switching element is connected to the control unit through the third resistor, for receiving a third control signal sent by the control unit, and controlling the location according to the third control signal The first pole of the third three-terminal controllable switching element and the second pole of the third three-terminal controllable switching element are connected or disconnected, thereby controlling the second load to communicate with or disconnect from the battery.

In a second aspect, the embodiment of the present application provides a monitoring and control method for a battery load capacity, which is applied to the above-mentioned battery load capacity monitoring and control system, and the method includes:

The control unit controls the measurement load to be disconnected from the battery and acquire the first of the battery Output voltage value;

The control unit controls the measurement load to communicate with the battery, and acquires a second output voltage value of the battery;

The control unit determines a resistance value of an internal resistance of the battery according to the first output voltage value, the second output voltage value, and a resistance value of the measurement load; and further, according to the first output voltage value, Determining, by the second output voltage value, a resistance value of an internal resistance of the battery, a quiescent current value flowing through the control unit, and a resistance value of the measurement load, in combination with a discharge curve of the battery, determining the battery Remaining capacity.

Wherein, when the system further includes a first load unit, the method further includes:

The control unit controls the measurement load to be disconnected from the battery and the first load is in communication with the battery, and acquires a third output voltage value of the battery;

The control unit determines an impedance value of the first load according to the first output voltage value, the third output voltage value, and the resistance of the internal resistance.

Wherein, when the system further includes a second load unit, the method further includes:

The control unit controls the measurement load and the first load to be disconnected from the battery and the second load to communicate with the battery, and acquire a fourth output voltage value of the battery;

The control unit determines an impedance value of the second load according to the first output voltage value, the fourth output voltage value, and the resistance of the internal resistance.

The method further includes:

When the control unit controls the measurement load, the first load and the second load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold, an alarm is generated;

When the control unit controls the measurement load to communicate with the battery and the first load and the second load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold And controlling the measurement load to be disconnected from the battery; and/or

When the control unit controls the first load to communicate with the battery and the second load and the measurement load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold a value that controls the first load to be disconnected from the battery; and/or

When the control unit controls the second load to communicate with the battery and the first load and the measurement load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold And controlling the second load to be disconnected from the battery.

The beneficial effects of the embodiments of the present application are as follows: The method and system for monitoring and controlling the battery load capacity provided by the embodiments of the present application, by adding a specific measurement load when detecting the battery voltage, and measuring the real-time resistance of the internal resistance of the battery in combination with the measurement load In combination with the real-time resistance value, the battery load capacity and the current battery power are calculated, which can effectively avoid the battery floating pressure, improve the accuracy of the battery voltage detection, and display the remaining capacity of the battery more stably. Further, by measuring the real-time internal resistance of the battery, the impedance of each real load of the system is measured and stored as a load characteristic value in the system, so that the number of the system "core" can be better realized. Monitoring and control of the load capacity of the battery; by combining the real-time internal resistance of the battery with the impedance of the real load, further assessing the load capacity of the battery and predicting the impact of the load start on the system and correspondingly processing according to the evaluation results, can prevent overload Causes system problems.

DRAWINGS

The one or more embodiments are exemplified by the accompanying drawings in the accompanying drawings, and FIG. The figures in the drawings do not constitute a scale limitation unless otherwise stated.

1 is a circuit diagram of a prior art for measuring an output voltage of a battery;

2 is a circuit diagram of a monitoring and control system for battery load capacity provided by an embodiment of the present application;

Figure 3 is a circuit diagram of the measurement load switch drive circuit shown in Figure 2;

4 is a circuit diagram of a monitoring and control system for battery load capacity according to another embodiment of the present application;

Figure 5 is a circuit diagram of the first load switch drive circuit shown in Figure 4;

Figure 6 is a circuit diagram of the second load switch drive circuit shown in Figure 4;

7 is a flowchart of a method for monitoring and controlling battery load capacity provided by an embodiment of the present application; as well as,

Fig. 8 is a graph showing a 0.5 C charge and discharge curve of a battery having a capacity of 800 mAH.

detailed description

In order to make the objects, technical solutions, and advantages of the present application more comprehensible, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the application and are not intended to be limiting. Further, the technical features involved in the various embodiments of the present application described below may be combined with each other as long as they do not constitute a conflict with each other.

The battery is a basic DC power source in electronic equipment, which has a capacity limitation. Therefore, the output voltage and remaining capacity of the battery must be monitored in real time to prevent the system from being unstable or abnormal due to overload. Generally, in the prior art, as shown in FIG. 1, the voltage value V_AD is sampled by a resistor division method, and then the voltage value V_AD is digital-to-analog converted, and the output voltage value of the battery is calculated, and finally, according to the output of the battery. The voltage value and the charge and discharge curve of the battery estimate the remaining capacity of the battery. However, in practical applications, the internal circuit of the battery is equivalent to an ideal voltage source and an internal resistance in series with the ideal voltage source, and the resistance of the internal resistance increases as the battery power decreases. Due to the internal resistance of the battery, when the battery is powered by different loads, if the output voltage value of the battery is obtained by using the existing technology, the output voltage value of the obtained battery may appear to be large and small, and accordingly, if the device If there is a battery level display, there will be a situation where the battery is more charged for a while. Further, as the battery power decreases, the internal resistance increases, and the load capacity thereof drops sharply. The above problem is more obvious, and when the load is switched from light load to heavy load, the system is unstable.

Based on this, the embodiment of the present application provides a monitoring and control method and system for battery load capacity. The method and system calculate the battery load capacity and the current battery power based on the real-time internal resistance of the battery, which can effectively prevent the battery from floating. The pressure increases the accuracy of the battery voltage detection, thereby more stably displaying the remaining capacity of the battery.

Specifically, as shown in FIG. 2, the embodiment of the present application provides a monitoring and control system 10 for battery load capacity, the system 10 including: a control unit 11 connected in parallel with the battery 20 to be detected, and a parallel connection with the battery 20. The load unit 12 is measured, wherein the measurement load unit 12 includes a measurement load 121 and a measurement load switch drive circuit 122 connected to the measurement load 121, the measurement load switch drive circuit The control unit 11 is connected to the control unit 11 for receiving the first control signal sent by the control unit 11, and controls the measurement load 121 to communicate with or disconnect from the battery 20 according to the first control signal; the control unit 11 is configured to control the measurement load 121. Obtaining a first output voltage value of the battery 20 when the battery 20 is disconnected, and acquiring a second output voltage value of the battery 20 when controlling the measurement load 121 to communicate with the battery 20, and according to the first output voltage value, The second output voltage value and the resistance value of the measurement load determine a resistance value of the internal resistance of the battery 20, according to the first output voltage value, the second output voltage value, the resistance of the internal resistance of the battery, The quiescent current value flowing through the control unit and the resistance value of the measurement load are combined with the discharge curve of the battery to determine the remaining capacity of the battery.

In the embodiment of the present application, according to the "Davinan theorem", the battery 20 to be detected can be equivalent to the series ideal ideal voltage source 21 without internal resistance and the battery internal resistance 22, and the control unit 11 is equivalent to have specific The quiescent current value of the two-terminal network, wherein the quiescent current value is the system quiescent operating current, which can be measured during product commissioning and/or trial production. The control unit 11 may be any one or more of a system control circuit, a power control conversion circuit, a measurement circuit, and the like. The measurement load unit 12 is used to assist in measuring the resistance of the internal resistance 22 of the current battery 20.

In the embodiment of the present application, when monitoring the battery loading capacity, the battery 20 is connected in parallel with the control unit 11 and the measurement load unit 12, and the control unit 11 sends a first control signal to the measurement load unit 12 according to the instruction input by the detection personnel. The measurement load switch driving circuit 122 is configured to control the measurement load 121 to communicate with or disconnect from the battery 20, and when the first control signal is “connecting the measurement load 121 and the battery 20”, the measurement load is measured. The switch driving circuit 122 controls the measurement load 121 to communicate with the battery 20 according to the first control signal; when the first control signal is “breaking the measurement load 121 and the battery 20”, the measurement load switch driving circuit 122 is configured according to the first control signal. The measurement load 121 is controlled to be disconnected from the battery 20.

In the embodiment of the present application, the measurement load 121 is introduced in the battery load carrying capacity monitoring control system 10, and the measurement load 121 and the battery 20 are controlled according to the first control signal sent by the control unit 11 by the measurement load switch drive circuit 122. Connected or disconnected, the voltage value (ie, the first output voltage value) outputted by the battery 20 without the measurement load 12 and the voltage value (ie, the second output voltage value) outputted when the measurement load 121 is measured can be obtained, thereby obtaining The real-time resistance of the internal resistance 22 of the current battery 20 can be used to calculate the load capacity of the battery and the current battery capacity based on the real-time internal resistance of the battery, effectively avoiding the battery floating pressure, improving the accuracy of the battery voltage detection, and thereby being more stable. The ground shows the remaining capacity of the battery.

Specifically, as shown in FIG. 3, the measurement load switch drive circuit 122 includes a first three-terminal controllable switching element 1221 and a first resistor 1222. The first pole of the first three-terminal controllable switching element 1221 is connected to the positive terminal of the battery 20 through the measuring load 121; the second pole of the first three-terminal controllable switching element 1221 is connected to the negative terminal of the battery 20; The control electrode of the three-terminal controllable switching element 1221 is connected to the control unit 11 through the first resistor 1222, and is configured to receive the first control signal sent by the control unit 11, and control the first three-terminal controllable switch according to the first control signal. The first pole of the component 1221 and the second pole of the first three-terminal controllable switching component 1221 are turned on or off, thereby controlling the measurement load 121 to be in communication with or disconnected from the battery 20. In the embodiment of the present application, the first three-terminal controllable switching element 1221 controls the connection or disconnection between the measurement load 121 and the battery 20, and the implementation manner is simple and convenient, and the cost of the system 10 can be reduced; The first resistor 1222 is connected between the control switching element 122 and the control unit 11, which can provide a stable static working point for the control pole of the first three-terminal controllable switching element 1221, and improve the stability of the system 10.

Further, as shown in FIG. 4, another embodiment of the present application provides a battery load carrying capacity monitoring and control system 30. The system 30 further includes, relative to the system 10, a first load in parallel with the battery 20. Unit 31 and second load unit 32. The first load unit 31 includes a first load 311 and a first load switch drive circuit 312. The first load switch drive circuit 312 is connected to the control unit 11 for receiving the second control signal sent by the control unit 11, and The second control signal controls the first load 311 to communicate with or disconnect from the battery 20; the second load unit 32 includes a second load 321 and a second load switch drive circuit 322, and the second load switch drive circuit 322 and control The unit 11 is connected to receive a third control signal sent by the control unit 11, and controls the second load 321 to communicate with or disconnect from the battery 20 according to the third control signal. The first load 311 and the second load 321 in the first load unit 31 and the second load unit 32 are real loads in the system 30. It should be understood that the embodiment of the present application is only described by taking two real load units as an example, but is not used to limit the present application. In an actual application, the real load unit may include one or more, for example, the system 30 may only The first load unit 31 or the second load unit 32 is connected in parallel with the battery 20, or the system 30 may include a third load unit in parallel with the battery 20, in addition to the first load unit 31 and the second load unit 32, The fourth load unit, the fifth load unit, and the like. In this embodiment, the control unit 11 is further configured to: control the measurement load 121 to be disconnected from the battery 20 and the first load 311 is in communication with the battery 20, and acquire a third output voltage value of the battery 20, and according to the first output Determining the impedance value of the first load 311 by the voltage value, the third output voltage value, and the resistance of the internal resistance; or controlling the measurement load 121 and the first The load 311 is disconnected from the battery 20 and the second load 321 is in communication with the battery 20, and acquires a fourth output voltage value of the battery 20, and according to the first output voltage value, the fourth output voltage value, and the inner The resistance value of the resistor determines the impedance value of the second load 321.

In this embodiment, by using the measurement load unit to measure the real-time internal resistance of the battery, the impedance of each real load of the system is further measured by the first load unit 31 and/or the second load unit 32 as the load characteristic value. Stored in the system, it can pre-evaluate the impact of the starting load on the battery power, so that the system has a number of "cores" in the load, better realize the monitoring and control of the battery's load capacity; by combining the real-time internal resistance of the battery and the real The impedance of the load further evaluates the load capacity of the battery and predicts the impact that the load can initiate on the system and processes it accordingly, preventing overload and causing system problems.

Specifically, as shown in FIG. 5, the first load switch driving circuit 312 includes a second three-terminal controllable switching element 3112 and a second resistor 3122. The first pole of the second three-terminal controllable switching component 3121 is connected to the positive terminal of the battery 20 through the measuring load 311; the second pole of the second three-terminal controllable switching component 3121 is connected to the negative terminal of the battery 20; The control pole of the three-terminal controllable switching element 3121 is connected to the control unit 11 through the second resistor 3122, for receiving the second control signal sent by the control unit 11, and controlling the second three-terminal controllable switch according to the second control signal. The first pole of the component 3121 and the second pole of the second three-terminal controllable switching component 3121 are turned on or off, thereby controlling the first load 311 to communicate with or disconnect from the battery 20. In the embodiment of the present application, the second load and disconnection of the first load 311 and the battery 20 are controlled by the second three-terminal controllable switching element 3121, which is simple and convenient to implement, and can reduce the cost of the system 30; The second resistor 3122 is connected between the controllable switching element 312 and the control unit 11, which can provide a stable static working point for the control pole of the second three-terminal controllable switching element 3121, and improve the stability of the system 30.

Specifically, as shown in FIG. 6, the second load switch driving circuit 322 includes a third three-terminal controllable switching element 3221 and a third resistor 3222. The first pole of the third three-terminal controllable switching element 3221 is connected to the positive terminal of the battery 20 through the measuring load 321; the second pole of the third three-terminal controllable switching element 3221 is connected to the negative terminal of the battery 20; The control pole of the three-terminal controllable switching element 3221 is connected to the control unit 11 through the third resistor 3222, for receiving the third control signal sent by the control unit 11, and controlling the third three-terminal controllable switch according to the third control signal. The first pole of the component 3221 and the second pole of the third three-terminal controllable switching component 3221 are turned on or off, thereby controlling the second load 321 to communicate with the battery 20 or disconnect. In the embodiment of the present application, the connection or disconnection of the second load 321 and the battery 20 is controlled by the third three-terminal controllable switching element 3221, which is simple and convenient to implement, and can reduce the cost of the system 30; The third resistor 3222 is connected between the controllable switching element 322 and the control unit 11, which can provide a stable static working point for the control pole of the third three-terminal controllable switching element 3221, and improve the stability of the system 30.

It should be noted that any one of the first three-terminal controllable switching element 1221, the second three-terminal controllable switching element 3121, and the third three-terminal controllable switching element 3221 may include, but is not limited to, a triode, a MOS tube, and an IGBT. (Insulated gate bipolar transistor), etc.

In addition, as shown in FIG. 7, the embodiment of the present application further provides a method for monitoring and controlling battery load capacity, which can be applied to the system 10 shown in FIG. 2 or the system 30 shown in FIG. The methods include:

S1. The control unit 11 controls the measurement load 121 to be disconnected from the battery 20 and acquires the first output voltage value of the battery 20.

In the embodiment of the present application, the measurement load switch drive circuit 122 controls the measurement load 121 to be disconnected from the battery 20 according to the first control signal ("off measurement load 121 and battery 20") issued by the control unit 11.

S3. The control unit 11 controls the measurement load 121 to communicate with the battery 20 and acquires a second output voltage value of the battery 20.

In the embodiment of the present application, the measurement load switch drive circuit 122 controls the measurement load 121 to communicate with the battery 20 according to the first control signal ("Connected Measurement Load 121 and Battery 20") issued by the control unit 11.

S5. The control unit 11 determines the resistance value of the internal resistance 22 of the battery 20 according to the first output voltage value, the second output voltage value, and the resistance value of the measurement load 121, and according to the first output voltage value and the second output voltage value. The resistance of the internal resistance 22, the quiescent current value flowing through the control unit 11, and the resistance of the measurement load 121 are combined with the discharge curve of the battery to determine the remaining capacity of the battery 20.

In the embodiment of the present application, according to the "Davinan theorem", the battery 20 can be equivalent to the series of ideal voltage source 21 without internal resistance and the internal resistance 22 of the battery, and the voltage value of the ideal voltage source 21 is set to Vs, the battery The resistance of the internal resistance 22 is Rs, the output current value of the battery 20 is Is, and the output voltage of the battery 20 is Vbat. Wherein, the relationship between the above parameters satisfies the formula: Vbat=Vs-Rs*Is. Meanwhile, in the embodiment of the present application, the control unit 11 can also be equivalent to a two-terminal network having a specific quiescent current value, and set the quiescent current value flowing through the control unit 11 to Ist, wherein the quiescent current The value Ist is the static operating current of the system and can be measured during product commissioning and/or trial production. It should be noted that, in the embodiment of the present application, the quiescent current value Ist is assumed to be a constant value. In addition, in the embodiment of the present application, the measurement load 121 refers to a load of a specific known resistance added to the output end of the battery 20 by the tester for testing the load capacity of the battery 20, and the measurement load 121 is The resistance is recorded as R_load.

In the embodiment of the present application, in order to measure the resistance of the internal resistance 22, the control unit 11 controls the measurement load switch drive circuit 122 to control the output voltage of the battery 20 when the measurement load 121 is disconnected from the battery 20, and is recorded as the first output. Voltage value Vbat1. Where, under the test condition, Is=Ist, according to the formula Vbat=Vs-Rs*Is, Vbat1=Vs-Rs*Ist can be obtained.

The control unit 11 controls the measurement load switch drive circuit 122 to control the output voltage of the battery 20 when the measurement load 121 is in communication with the battery 20, and is recorded as the second output voltage value Vbat2. Under the test condition, Is=Ist+Ix, where Ix is the current flowing through the measurement load 121, according to the formula Vbat=Vs-Rs*Is, it can be obtained: Vbat2=Vs-Rs*(Ist+Ix); Further, in the circuit, it is known that the resistance value of the measurement load 121 is R_load, and it can be calculated from the volt-ampere characteristic: Ix=Vbat2/R_load, and further, Vbat2=Vs-Rs*(Ist+Vbat2/R_load).

Further, Vbat1-Vbat2=Rs*Ix can be obtained by combining the formula Vbat1=Vs-Rs*Ist and the formula Vbat2=Vs-Rs(Ist+Ix), and then can be calculated according to the formula Rs=(Vbat1-Vbat2)*R_load/Vbat2. The resistance value Rs of the internal resistance 22 is obtained; wherein, Vbat1 and Vbat2 are measurable, and R_load is a known fixed value.

In the embodiment of the present application, according to the first output voltage value Vbat1, the second output voltage value Vbat2, the resistance value Rs of the internal resistance 22, the quiescent current value Ist flowing through the control unit 11, and the resistance value R_load of the measurement load 121, and In conjunction with the discharge curve of the battery 20, the remaining capacity of the battery 20 is determined. The discharge curve of the battery 20 is a characteristic curve of the battery 20, and on the discharge curve of the battery 20, the output voltage value of the battery 20 has a one-to-one correspondence relationship with the remaining capacity of the battery 20, and therefore, when the battery is acquired When the voltage value is output, the remaining capacity of the battery 20 can be inquired in conjunction with the discharge curve of the battery 20. For example, as shown in FIG. 8, it is a 0.5C charge and discharge graph of a battery with a capacity of 800 mAH; according to the formula Vbat=Vs-Rs*Is, the output voltage of the battery 20 at a discharge current of 0.5 C is calculated as Vbat_0.5C. =Vs-Rs*I _0.5C , and further, Vbat_0.5C=Vbat2-Rs*(I _0.5C -Ix-Ist) is obtained from Vs=Vbat2+Rs*(Ix+Ist), wherein the quiescent current value Ist is debugged It can be measured in trial production, I _0.5C = 0.5 * 800 mA = 400 mA, Ix and Rs have been calculated in the above steps, namely Ix = Vbat2 / R_load, Rs = (Vbat1 - Vbat2) * R_load / Vbat2. Finally, according to the calculated output voltage Vbat_0.5C at 0.5C discharge current and the above 0.5C charge and discharge graph, the remaining capacity of the battery 20 can be queried to facilitate stable display on the electronic device provided with the system. The remaining capacity of the battery.

In addition, for the system 30 shown in FIG. 4, that is, when the system further includes the first load unit and/or the second load unit, the embodiment of the present application provides another monitoring and control method for the battery load capacity. In addition to the steps S1, S3 and S5 as described above, the method further comprises:

When the control unit 11 controls the measurement load 121 to be disconnected from the battery 20 and the first load 311 is in communication with the battery 20, the output voltage of the battery 20 is acquired and is recorded as the output three voltage value Vbat3. Wherein, under the test condition, Is=Ist+I1, wherein I1 is the current flowing through the first load 311, according to the formula Vbat=Vs-Rs*Is, it can be obtained: Vbat3=Vs-Rs(Ist+I1 In combination with Vbat1=Vs-Rs*Ist, the current I1=(Vbat1-Vbat3)/Rs flowing through the first load 311 can be calculated, and the resistance of the first load 311 is calculated to be RL1=Vbat3/I1=Vbat3*Rs. /(Vbat1-Vbat3), whereby the impedance value of the first load 311 can be determined. It should be noted that, theoretically, the voltage value Vs of the ideal voltage source 21 is gradually decreased as the battery 20 is used, but since the measurement interval of the output voltage Vbat of the battery 20 is extremely short, and it flows through In the case where the current I1 of the first load 311 is small, it can be assumed that the voltage value Vs of the ideal voltage source 21 is the same in the two measurements.

Similarly, when the control unit 11 controls the measurement load 121 and the first load 311 to be disconnected from the battery 20 and the second load 321 is in communication with the battery 20, the output voltage of the battery 20 is acquired and recorded as the fourth output voltage value Vbat4. . Wherein, under the test condition, Is=Ist+I2, wherein I2 is the current flowing through the second load 321, according to the formula Vbat=Vs-Rs*Is, it can be obtained: Vbat4=Vs-Rs(Ist+I2 In combination with Vbat1=Vs-Rs*Ist, the current I2=(Vbat1-Vbat4)/Rs flowing through the second load 321 can be calculated, and the resistance of the second load 321 is calculated to be RL2=Vbat4/I2=Vbat4*Rs. /(Vbat1-Vbat4), whereby the impedance value of the second load 321 can be determined.

In this embodiment, the first output voltage value Vbat1 and the second output voltage value Vbat2 of the battery 20 are obtained, and the resistance value Rs of the internal resistance 22, the impedance value RL1 of the first load 311, and the second load 321 are calculated. In the case of the impedance value RL2, I1=Vbat1/RL1; I2=Vbat1/RL2 can be approximated to estimate the current under different loads (first load or second load); and according to the equation Vbat=Vs-Rs*Is Out: Vbat=Vs-Rs(Ist+I1+I2+I3)=Vs-Rs*Ist-Rs(I1+I2+I3)=Vbat1-Rs(I1+I2+I3). Wherein, I1 and I2 are effective when the corresponding load is connected to the battery, and 0 is taken when the corresponding load is disconnected from the battery 20. Therefore, in the present embodiment, by acquiring the impedance values of the loads (the first load and the second load) in the system, the above formula can be used to pre-calculate the battery output voltage under a single load or multiple load combinations, and evaluate Whether the startup load will excessively lower the battery output voltage and cause the system voltage to be unstable, and determine whether to start the corresponding load according to the evaluation result, and take preventive measures to improve the reliability of the system.

In addition, in other embodiments, in order to ensure the stability of the system and the accuracy of the measurement result, when the load is first started to perform the monitoring control of the battery load capacity, it is first evaluated whether the start of the load excessively lowers the output of the battery. The voltage is then obtained by the voltage output from the battery 20 when the load is started. It should be noted that the “load” started here may be any one of the measurement load 121, the first load 311, and the second load 321, and the “starting load” refers to controlling the load to communicate with the battery 20 and other loads. Disconnected from the battery 20.

In this embodiment, the first step is to apply the system 30 shown in FIG. 4 to monitor and control the load capacity of the battery 20 as an example to explain this step:

When the control unit 11 controls the measurement load 121, the first load 311, and the second load 321 to be disconnected from the battery 20, if the output voltage of the battery 20 is less than a preset low-voltage alarm threshold, that is, if the first output voltage value Vbat1 is less than the pre- If the low voltage alarm threshold is set, the alarm is generated; if the first voltage value Vbat1 is greater than or equal to the preset low pressure alarm threshold, the first output voltage value Vbat1 is obtained.

When the control unit 11 controls the measurement load 121 to communicate with the battery 20 and both the first load 311 and the second load 321 are disconnected from the battery 20, if the output voltage of the battery 20 is less than a preset low pressure alarm threshold, the measurement load 121 is controlled. The battery 20 is disconnected and alarmed; if the output voltage of the battery 20 is greater than or equal to a preset low pressure alarm threshold, the measurement load 121 is kept in communication with the battery 20, and the second output voltage value Vbat2 of the battery 20 is obtained.

When the control unit 11 controls the first load 311 to communicate with the battery 20 and the second load 321 and the measurement load 121 are both disconnected from the battery 20, if the output voltage of the battery 20 is less than a preset low pressure alarm threshold, the first load 311 is controlled. Disconnected from the battery 20 and alarmed; if the output voltage of the battery 20 is greater than or equal to a preset low-voltage alarm threshold, the first load 311 is kept in communication with the battery 20, and the battery 20 is obtained. The third output voltage value is Vbat3.

When the control unit 11 controls the second load 321 to communicate with the battery 20 and both the first load 311 and the measurement load 121 are disconnected from the battery 20, if the output voltage of the battery 20 is less than a preset low pressure alarm threshold, the second load 321 is controlled. Disconnected from the battery 20 and alarmed; if the output voltage of the battery 20 is greater than or equal to the preset low voltage alarm threshold, the second load 321 is kept in communication with the battery 20, and the fourth output voltage value Vbat4 of the battery 20 is obtained.

According to the foregoing technical solution, the beneficial effects of the embodiment of the present application are as follows: the monitoring and control method for the battery load capacity provided by the embodiment of the present application detects the internal resistance of the battery by adding a specific measurement load when detecting the battery voltage, and measuring the load with the measurement load. The real-time resistance value, combined with the real-time resistance value, to calculate the load capacity of the battery and the current power of the battery, can effectively avoid the battery floating pressure, improve the accuracy of the battery voltage detection, and more stably display the remaining capacity of the battery; By measuring the real-time internal resistance of the battery, the impedance of each real load of the system is measured and stored as a load characteristic value in the system, which enables the system to have a number of "cores" in the load, and better realize the battery. Monitoring and control of the load capacity; by combining the real-time internal resistance of the battery with the impedance of the real load, further assessing the load capacity of the battery and predicting the impact of the load start on the system and correspondingly processing according to the evaluation results, can prevent the system from being overloaded problem.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; in the idea of the present application, the technical features in the above embodiments or different embodiments may also be combined. The steps may be carried out in any order, and there are many other variations of the various aspects of the present application as described above, which are not provided in the details for the sake of brevity; although the present application has been described in detail with reference to the foregoing embodiments, The skilled person should understand that the technical solutions described in the foregoing embodiments may be modified, or some of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the embodiments of the present application. The scope of the technical solution.

Claims (10)

1. A monitoring and control system for battery load capacity, characterized in that the system comprises:

   a control unit and a measurement load unit, wherein the control unit and the measurement load unit are respectively connected in parallel with a battery to be detected; wherein the measurement load unit comprises a measurement load and a measurement load switch drive circuit connected to the measurement load;

   The measuring load switch driving circuit is connected to the control unit, and configured to receive a first control signal sent by the control unit, and control the measuring load to communicate with or disconnect from the battery according to the first control signal;

   The control unit is configured to acquire a first output voltage value of the battery when controlling the measurement load to be disconnected from the battery, and acquire a quantity of the battery when controlling the measurement load to communicate with the battery And outputting a voltage value, and determining a resistance value of the internal resistance of the battery according to the first output voltage value, the second output voltage value, and a resistance value of the measurement load; and further, according to the first output a voltage value, the second output voltage value, a resistance value of an internal resistance of the battery, a quiescent current value flowing through the control unit, and a resistance value of the measurement load, and determined in combination with a discharge curve of the battery The remaining capacity of the battery.
2. The system according to claim 1, wherein said measuring load switch driving circuit comprises: a first three-terminal controllable switching element and a first resistor;

   The first pole of the first three-terminal controllable switching element is connected to the positive terminal of the battery through the measuring load;

   The second pole of the first three-terminal controllable switching element is connected to the negative terminal of the battery;

   The control pole of the first three-terminal controllable switching element is connected to the control unit through the first resistor, and is configured to receive a first control signal sent by the control unit, and control the location according to the first control signal The first pole of the first three-terminal controllable switching element and the second pole of the first three-terminal controllable switching element are turned on or off, thereby controlling the measuring load to communicate with or disconnect from the battery.
3. The system of claim 1 wherein said system further comprises: a first load unit in parallel with said battery;

   The first load unit includes a first load and a first load switch drive circuit, the first load a switch driving circuit is connected to the control unit, configured to receive a second control signal sent by the control unit, and control the first load to communicate with or disconnect from the battery according to the second control signal;

   The control unit is further configured to control the measurement load to be disconnected from the battery and the first load is in communication with the battery, and acquire a third output voltage value of the battery, and according to the first output voltage The value, the third output voltage value, and the resistance of the internal resistance determine an impedance value of the first load.
4. The system of claim 3, wherein the first load switch drive circuit comprises: a second three-terminal controllable switching element and a second resistor;

   The first pole of the second three-terminal controllable switching element is connected to the positive terminal of the battery through the first load;

   The second pole of the second three-terminal controllable switching element is connected to the negative terminal of the battery;

   a control pole of the second three-terminal controllable switching element is connected to the control unit by the second resistor, for receiving a second control signal sent by the control unit, and controlling the second control signal according to the second control signal The first pole of the second three-terminal controllable switching element and the second pole of the second three-terminal controllable switching element are turned on or off, thereby controlling the first load to communicate with or disconnect from the battery.
5. The system of claim 3 or 4, wherein the system further comprises: a second load unit in parallel with the battery;

   The second load unit includes a second load and a second load switch drive circuit, and the second load switch drive circuit is coupled to the control unit for receiving a third control signal sent by the control unit, and according to the The third control signal controls the second load to be connected or disconnected from the battery;

   The control unit is further configured to control that the measurement load and the first load are both disconnected from the battery and the second load is in communication with the battery, and acquire a fourth output voltage value of the battery, and And determining an impedance value of the second load according to the first output voltage value, the fourth output voltage value, and the resistance of the internal resistance.
6. The system according to claim 5, wherein the second load switch driving circuit comprises: a third three-terminal controllable switching element and a third resistor;

   The first pole of the third three-terminal controllable switching element is connected to the positive terminal of the battery through the second load;

   The second pole of the third three-terminal controllable switching element is connected to the negative terminal of the battery;

   a control pole of the third three-terminal controllable switching element is connected to the control unit through the third resistor, for receiving a third control signal sent by the control unit, and controlling the location according to the third control signal The first pole of the third three-terminal controllable switching element and the second pole of the third three-terminal controllable switching element are connected or disconnected, thereby controlling the second load to communicate with or disconnect from the battery.
7. A method for monitoring and controlling a battery load capacity, which is applied to the system according to any one of claims 1 to 6, wherein the method comprises:

   The control unit controls the measurement load to be disconnected from the battery, and acquires a first output voltage value of the battery;

   The control unit controls the measurement load to communicate with the battery, and acquires a second output voltage value of the battery;

   The control unit determines a resistance value of an internal resistance of the battery according to the first output voltage value, the second output voltage value, and a resistance value of the measurement load; and further, according to the first output voltage value, Determining, by the second output voltage value, a resistance value of an internal resistance of the battery, a quiescent current value flowing through the control unit, and a resistance value of the measurement load, in combination with a discharge curve of the battery, determining the battery Remaining capacity.
8. The method of claim 7, wherein when the system further comprises a first load unit, the method further comprises:

   The control unit controls the measurement load to be disconnected from the battery and the first load is in communication with the battery, and acquires a third output voltage value of the battery;

   The control unit determines an impedance value of the first load according to the first output voltage value, the third output voltage value, and the resistance of the internal resistance.
9. The method according to claim 8, wherein when the system further comprises a second load unit, the method further comprises:

   The control unit controls the measurement load and the first load to be disconnected from the battery and the second load to communicate with the battery, and acquire a fourth output voltage value of the battery;

   The control unit is configured according to the first output voltage value, the fourth output voltage value, and the inner The resistance value of the resistor determines the impedance value of the second load.
10. The method of claim 9 wherein the method further comprises:

    When the control unit controls the measurement load, the first load and the second load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold, an alarm is generated;

    When the control unit controls the measurement load to communicate with the battery and the first load and the second load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold And controlling the measurement load to be disconnected from the battery; and/or,

    When the control unit controls the first load to communicate with the battery and the second load and the measurement load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold And controlling the first load to be disconnected from the battery; and/or,

    When the control unit controls the second load to communicate with the battery and the first load and the measurement load are both disconnected from the battery, if the output voltage of the battery is less than a preset low pressure alarm threshold And controlling the second load to be disconnected from the battery.

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